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The Middle Sepik languages comprise diverse groups of Sepik languages spoken in northern Papua New Guinea. The Middle Sepik grouping is provisionally accepted by Foley (2018) based on shared innovations in pronouns, but is divided by Glottolog. They are spoken in areas surrounding the town of Ambunti in East Sepik Province.
Unlike most other Sepik languages, Middle Sepik languages do not overtly mark gender on nouns, although the third-person singular pronoun does distinguish between masculine and feminine genders (e.g., Proto-Ndu *nd- '3SG.M' and *l- '3SG.F').
Foley, William A. (2018). "The Languages of the Sepik-Ramu Basin and Environs". In Palmer, Bill (ed.). The Languages and Linguistics of the New Guinea Area: A Comprehensive Guide. The World of Linguistics. Vol. 4. Berlin: De Gruyter Mouton. pp. 197–432. ISBN978-3-11-028642-7.
Ross, Malcolm (2005). "Pronouns as a preliminary diagnostic for grouping Papuan languages". In Andrew Pawley; Robert Attenborough; Robin Hide; Jack Golson (eds.). Papuan pasts: cultural, linguistic and biological histories of Papuan-speaking peoples. Canberra: Pacific Linguistics. pp. 15–66. ISBN0858835622. OCLC67292782.